A well-informed mind is the best security against the contagion of folly and of vice. The vacant mind is ever on the watch for relief, and ready to plunge into error, to escape from the languor of idleness.
The deadliest contagion is majority opinion.
If you had the seeds of pestilence in your body you would not have a more active contagion that you have in your tempers, tastes, and principles. Simply to be in this world, whatever you are, is to exert an influence, compared with which mere language and persuasion are feeble.